Facebook is best known for its blue hue, but on October 20, the site is embracing a new color: purple.

To commemorate the second annual Spirit Day, which is dedicated to supporting lesbian, gay, bisexual and transgender youth as well as fighting bullying and harassment, Facebook is partnering with the Gay and Lesbian Alliance Against Defamation (GLAAD) to encourage its employees and users to post purple profile photos on Facebook.

According to GLAAD, the color purple represents "spirit" on the rainbow flag and "wearing purple on this day symbolizes support for LGBT people and against bullying of LGBT teens."

GLAAD has created a Spirit Day site that offers people ways to "purple" their Facebook pictures, Twitter avatars, Google+ photos and more. Users that sync their social media accounts will be able to instantly add a purple hue to their profile pictures.

AT&T, Yahoo, Hewlett-Packard, Comcast and Viacom are among the other technology companies that plan to participate in Spirit Day. AT&T, for example, will light its headquarters in purple on October 20 and encourage employees to wear purple, while Yahoo plans to take photos of employees dressed in purple in the company's offices around the country.

Facebook has launched several initiatives that specifically aim to stop bullying online and support the LGBT community. Last year, Facebook joined forces with five LGBT advocacy organizations that "serve in a consultative capacity to help Facebook effectively address issues faced by the LGBT community" and comprise the company's Network of Support group.